Effect of Reverberation Time on Vocal Fatigue

Vocal effort is a physiological magnitude that accounts for the changes in voice production that occur as vocal loading, which is the stress inflicted on the vocal folds when speaking for long periods, increases. It has been quantified in terms of Sound Pressure Level (SPL). In previous research, it has been shown that prolonged vocal effort can lead to vocal fatigue. An experiment was conducted to measure the effect of reverberation time on vocal fatigue, by means of an evaluation of variation in vocal effort over time. Twenty subjects were recorded while reading a text in anechoic, semi-reverberant and reverberant rooms in the presence of babble noise. Withinsubject variation in SPL was measured per task. It was found that SPL tended to increase less over time in the semireverberant environment than in the anechoic or reverberant environments. This finding suggests that subjects experienced less short-term vocal fatigue in the semi-reverberant environment.